Hi Dmitry and Greg It doesn't make sense to take a reference to our own module. When we call module_put(THIS_MODULE) we cannot make sure that our module is still alive when this function returns. Therefore, module_put() will return to invalid memory and our input_dev_release() function is no longer available. It would be interesting if Greg could elaborate what else we could do to replace this module-refcount as it is definitely needed here. However, "struct device" doesn't provide an owner field so there is no way for us to let the device core keep a reference to our module. I have no clue what to do here but the current implementation is definitely unsafe so this is marked as RFC. Currently, the device_attributes probably already keep a reference to our module so applying this patch would probably not break anything, however, this does not look like something we can trust on. My bug-thread kind of died (https://lkml.org/lkml/2011/10/29/75) so I now try to show this with an example here. Regards David Signed-off-by: David Herrmann <dh.herrmann@xxxxxxxxxxxxxx> --- drivers/input/input.c | 4 ---- 1 files changed, 0 insertions(+), 4 deletions(-) diff --git a/drivers/input/input.c b/drivers/input/input.c index da38d97..f691502 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -1417,8 +1417,6 @@ static void input_dev_release(struct device *device) input_mt_destroy_slots(dev); kfree(dev->absinfo); kfree(dev); - - module_put(THIS_MODULE); } /* @@ -1657,8 +1655,6 @@ struct input_dev *input_allocate_device(void) spin_lock_init(&dev->event_lock); INIT_LIST_HEAD(&dev->h_list); INIT_LIST_HEAD(&dev->node); - - __module_get(THIS_MODULE); } return dev; -- 1.7.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
